qml.fermi.FermiA¶

class FermiA(orbital)[source]¶

Bases: pennylane.fermi.fermionic.FermiWord

The fermionic annihilation operator $a$

For instance, the operator qml.FermiA(2) denotes $a_2$ . This operator applied to $\ket{0010}$ gives $\ket{0000}$ .

Parameters: orbital (int) – the non-negative integer indicating the orbital the operator acts on.

Note

While the FermiA class represents a mathematical operator, it is not a PennyLane qubit Operator.

See also

Example

To construct the operator $a_0$ :

>>> w = FermiA(0)
>>> print(w)
a(0)

This can be combined with the creation operator FermiC. For example, $a^{\dagger}_0 a_1 a^{\dagger}_2 a_3$ can be constructed as:

>>> w = qml.FermiC(0) * qml.FermiA(1) * qml.FermiC(2) * qml.FermiA(3)
>>> print(w)
a⁺(0) a(1) a⁺(2) a(3)

Methods

Return the adjoint of FermiA.